Studies on Choanephoraceae. IV. Carbon requirements

Summary The comparative utilization of different carbon compounds byBlakeslea trispora, Choanephora cucurbitarum, Choanephora infundibulifera, Choanephora conjuncta, Choanephora heterospora andChoanephora circinans was studied under controlled conditions. Of the monosaccharides, rhamnose and sorbose were poorly utilized, while the rest of them were favourably utilized by all the species. Amongst the disaccharides, maltose proved to be the best. Sucrose, lactose and melibiose were poor sources. Raffinose, the only trisaccharide used supported poor growth of all the species. Of the polysaccharides used, starch and glycogen supported good growth of all the species. Dextrin and inulin were used in varying degrees by the present species. Both sorbitol and mannitol supported growth of the fungi in varying degrees. All the organic acids used, proved to be valueless in the present investigation.In some cases good sporulation was accompanied with good or moderate growth. No correlation with regard to the growth and sporulation could be established. The final pH of media showed a tendency to drift towards the alkaline side in most of the cases.     

The utilization of the mixtures of monosaccharides by some mucorales

Summary The utilization of mixtures of monosaccharides byBlakeslea trispora Thaxter,Choanephora circinans (Naganish &Kawakami)Hesseltine &Benjamin,Gilbertella persicaria var.indica Mehrotra &Mehrotra andHelicostylum piriforme Bainier was studied. The effect of sorbose on the utilization of other sugars present in the mixtures was also studied. It was found that all the mixtures of sugars in combination with asparagine or ammonium chloride were valueless for all the organisms exceptHelicostylum piriforme. Growth ofHelicostylum piriforme on the mixtures with asparagine as the nitrogen source was better than on the mixtures with ammonium chloride as the source of nitrogen. Asparagine being a favourable source counteractecd sorbose inhibition, while ammonium chloride failed to do so. On the other hand, both of the nitrogen sources failed to counteract sorbose inhibition in the rest of the organisms. None of the organisms could finish sorbose and rhamnose from any of the mixtures within the specified period.     

Testing against Ordered Alternatives in One-way Layout

In this paper we investigate a simple method of modifying well known nonparametric tests for the several samples location problem to yield a class of test statistics suitable for ordered alternatives. Optimum member of the class is identified in each case and its efficacy obtained. The method is applied to five statistics.     

Molecular docking and simulation of Curcumin with Geranylgeranyl Transferase1 (GGTase1) and Farnesyl Transferase (FTase)

Protein prenylation is a posttranslational modification that is indispensable for translocation of membrane GTPases like Ras, Rho, Ras etc. Proteins of Ras family undergo farnesylation by FTase while Rho family goes through geranylgeranylation by GGTase1. There is only an infinitesimal difference in signal recognition between FTase and GGTase1. FTase inhibitors mostly end up selecting the cells with mutated Ras proteins that have acquired affinity towards GGTase1 in cancer microcosms. Therefore, it is of interest to identify GGTase1 and FTase dual inhibitors using the docking tool AutoDock Vina. Docking data show that curcumin (from turmeric) has higher binding affinity to GGTase1 than that of established peptidomimetic GGTase1 inhibitors (GGTI) such as GGTI-297, GGTI-298, CHEMBL525185. Curcumin also interacts with FTase with binding energy comparable to co-crystalized compound 2-[3-(3-ethyl-1-methyl-2-oxo-azepan-3-yl)-phenoxy]-4-[1-amino-1-(1-methyl-1h-imidizol-5-yl)-ethyl]-benzonitrile (BNE). The docked complex was further simulated for 10 ns using molecular dynamics simulation for stability. Thus, the molecular basis for curcumin binding to GGTase1 and FTase is reported.     

Synthesis,characterization and in vitro biological evaluation of some novel 1,3,5-triazine–Schiff base conjugates as potential antimycobacterial agents

A series of some novel 1,3,5-triazine–Schiff base conjugates (1–32) have been synthesized and evaluated for their in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv using Alamar Blue assay and the activity expressed as the minimum inhibitory concentration (MIC) in μg/mL. Compounds 4 (4-Methoxy-6-methyl-N-(3,4,5-trimethoxybenzylidene)-1,3,5-triazin-2-amine), 11 (4-Methoxy-6-methyl-N-(2-hydroxy-3-bromo-5-chloro-benzylidene)-1,3,5-triazin-2-amine) and 24 (4-Methoxy-6-methyl-N-(1-(2,5-dihydroxyphenyl)ethylidene)-1,3,5-triazin-2-amine) exhibited a significant activity at 3.125, 6.25 and 6.25 μg/mL, respectively, when compared with the antitubercular drugs such as ethambutol (3.125 μg/mL), pyrazinamide (6.25 μg/mL) and streptomycin (6.25 μg/mL) and it could be a potential starting point to develop new lead compounds in the fight against Mycobacterium tuberculosis H37Rv.     

Transformations of acetates of citronellol,geraniol, and linalool by Aspergillus niger: regiospecific hydroxylation of citronellol by a cell-free system

Summary Incubation of acetates of geraniol, citronellol and linalool with Aspergillus niger resulted in their hydrolysis to corresponding alcohols which were further hydroxylated to their respective 8-hydroxy derivatives. In the case of linalyl acetate, besides linalool and 8-hydroxylinalool, small amounts of geraniol and -terpineol were also formed. Microsomes (105 000xg sediment) prepared from induced cells of A. niger were found to convert (1-³H)citronellol to 8-hydroxy citronellol in the presence of NADPH and O₂. The pH optimum for the hydroxylase was found to be 7.6.     

From Clinging to Digging: The Postembryonic Skeletal Ontogeny of the Indian Purple Frog,Nasikabatrachus sahyadrensis (Anura: Nasikabatrachidae)

The Indian Purple frog, Nasikabatrachus sahyadrensis, occupies a basal phylogenetic position among neobatrachian anurans and has a very unusual life history. Tadpoles have a large ventral oral sucker, which they use to cling to rocks in torrents, whereas metamorphs possess adaptations for life underground. The developmental changes that underlie these shifts in habits and habitats, and especially the internal remodeling of the cranial and postcranial skeleton, are unknown. Using a nearly complete metamorphic series from free-living larva to metamorph, we describe the postembryonic skeletal ontogeny of this ancient and unique monotypic lineage. The torrent-dwelling larva possesses a dorsoventrally flattened body and a head with tiny dorsal eyes, robust lower and upper jaw cartilages, well-developed trabecular horns, and a definable gap between the trabecular horns and the tip of the snout. Unlike tadpoles of many other frogs, those of Nasikabatrachus retain larval mouthparts into late metamorphic stages. This unusual feature enables the larvae to maintain their clinging habit until near the end of metamorphosis. The subsequent ontogenetic shift from clinging to digging is correlated with rapid morphological changes and behavioral modifications. Metamorphs are equipped with a shortened tibiafibula and ossified prehallical elements, which likely facilitate initial digging using the hind limbs. Subsequently, the frogs may shift to headfirst burrowing by using the wedge-shaped skull, anteriorly positioned pectoral girdle, well-developed humeral crests and spatula-shaped forelimbs. The transition from an aquatic life in torrents to a terrestrial life underground entails dramatic changes in skeletal morphology and function that represent an extreme in metamorphic remodeling. Our analysis enhances the scope for detailed comparative studies across anurans, a group renowned for the diversity of its life history strategies.     

Stat3 Signaling Promotes Survival And Maintenance Of Medullary Thymic Epithelial Cells

Medullary thymic epithelial cells (mTECs) are essential for establishing central tolerance by expressing a diverse array of self-peptides that delete autoreactive thymocytes and/or divert thymocytes into the regulatory T cell lineage. Activation of the NFκB signaling pathway in mTEC precursors is indispensable for mTEC maturation and proliferation resulting in proper medullary region formation. Here we show that the Stat3-mediated signaling pathway also plays a key role in mTEC development and homeostasis. Expression of a constitutively active Stat3 transgene targeted to the mTEC compartment increases mTEC cellularity and bypasses the requirement for signals from positively selected thymocytes to drive medullary region formation. Conversely, conditional deletion of Stat3 disrupts medullary region architecture and reduces the number of mTECs. Stat3 signaling does not affect mTEC proliferation, but rather promotes survival of immature MHCII^loCD80^lo mTEC precursors. In contrast to striking alterations in the mTEC compartment, neither enforced expression nor deletion of Stat3 affects cTEC cellularity or organization. These results demonstrate that in addition to the NFkB pathway, Stat3-mediated signals play an essential role in regulating mTEC cellularity and medullary region homeostasis.